Antisiphoning means for dishwashing machines



June 20, 1950 R. w. WILSON ANTISIPHONING MEANS FOR DISHWASHING MACHINES Filed Sept. 27, 1944 INVENTOR. RAYMOND W. WILSON A TTORNE 1 Patented June 20, 1950 UNITED STATES mm OFFICE AN TISIPHONIN G MEANS FOR DISHWASHING MACHINES Raymond w. Wilson, Glendale, Calif. Application September 27, 1944, Serial No. 555,983

2 Claims. (01. 134-141) The present invention relates to improvements in antisyphoning means for washing machines and particularly to a conduit structure embodying such a means applicable to a machine of the dishwashing class as disclosed in Patent #2,315,572 issued to me April 6, 1943.

Under certain unusual conditions according to the health authorities it is possible to have a vacuum occur at the water valve instead of the usual pressures so that if certain conditions obtain, contaminated water from the drain, tub or piston chamber might be drawn into the city water lines which is forbidden.

An air gap positioned between the aforementioned parts would render such afeedback impossible.

One of the objects of the invention is to provide a conduit structure for washing machines which will prevent any possibility of a cross flow connection being made between the city water supply which operates the device and the drainage or sewage system whereby foul water might be syphoned back into the main supply line and contaminate it due principally to the unusual conditions aforementioned.

A further object is to improve upon the sanitary conditions relating to devices to which this invention appertains.

A further object is to provide improved means whereby a lower point of overflow of a backed-up sewer is effected than the normal rim overflow of the fixture communicating with the sewer.

A further object is to provide improved means to indicate when a defectiveness exists in certain of the associated plumbing parts.

A still further object is to provide improved means for obtaining a more positive purging and cleansing of certain parts of the apparatus with which the conduit structure is connected.

Yet a further object is to be able to ascertain when serious leaks occur in certain gaskets by observing discolorations in the water passing by the sight opening in the antisyphonlng device which the liquid spirts past.

Other objects, advantages and features of invention will hereinafter appear.

Referring to the drawing which illustrates what at present is deemed to be a preferred embodiment of the invention,

Fig. 1 is a fragmentary plan view of a sink and z dishwashing machine with which the conduit structure is related, the dish basket being removed and certain portions being broken away to disclose underlying structures.

Fi 2 is a vertical section taken on line 2-2 of Fig. 1 showing the conduit structure connected to the dishwashing machine, the dish basket being added in this view and shown in dotted and full lines in two different positions.

Fig. 3 is an enlarged elevational view of an antisyphoning means forming a part of the conduit structure, some parts being broken away and other parts sectioned.

Fig. 4 is a horizontal section taken on line 4-4 of Fig. 2.

Fig. 5 is a transverse section taken through the three way valve shown in Figs. 1 and 2.

Fig. 6 is a fragmentary, vertical cross section taken through the lower end of the hydraulic lift.

Referring in detail to the drawing, therein is shown a sink 6 having associated therewith a hydraulically operated dishwashing machine I, the sink emptying into a pipe 8 and the dishwashing machine emptying into a pipe 9, both of said pipes leading through the trap ll into the sewage line.

There is a hot and a cold water supply line connected to the sink, the hot and cold water conduits being indicated respectively by the numerals II and. I2. Conduit it connects the cold water line with a three way valve I4 situated at the right-rear of the wash tub l5 shown in Figs. 1 and 2.

To the underside of the tub I5 is shown connected the hydraulic lift l6 which actuates, through the medium of the water pressure, the upward movement of the dish basket ll.

Conduit l8 connects the three way valve It with the lower end ofthe lift I B, and conduit l9 connects the three way valve with the upper portion of the lift, the connection 20 of conduit I! with the lift being shown on an increased scale in Fig. 4. Diametrically opposite to the connection 2|! just described is a second connection 2| which is connected to conduit 22 and the latter conduit in turn is connected to the antispyhoning means 23 by an L 24. Connections 20 and to Fig. 8, to include the cylinder II and the plunger 2 closed by the cap 32 screwed thereonto, a pin 32 being secured to the cap to anchor the lower end of the spring. A double gasket 34 is shown sealing the'annular chamber 25 from the freshwater supply, the pressure from which exerts a force against the plunger to elevate it, the spring lis restoring it to normal position as soon as the three way valve is operated to relieve such pressure.

when port 35 is in registry with conduit I9 as shown in Fig. 5, the dish basket is in position to be elevated as soon as the three way valve is operated to bring the restricted port 36 in communication with conduit I3, port 36 being purposely made smaller in size to cause a slower elevating movement of the dish basket.

When the three way valve is in the position shown in Fig. 5, the fresh water from conduit I8 is discharged through conduit is around the annular passage 25, as seen in Fig. 4, to the oppo-, site conduit 22 and thence through the antisyphoning device 23 into the pipe 9 leading to the sewer. Hence .it will be observed that any leak to the annular space 25 from the tub I! can be detected owing to the discoloration of the water by looking at the discharged water asdt flows past the air gap provided by the diametrically opposite openings 31 in the antisyphoning device. This leak and discoloration of the water would not be so readily apparent if such discharge were partially by-passed by the annular chamber as shown by the T arrangement in the stated patent.

Neither would the chamber 25 be purged and cleansed so readily for the same'reason. Furthermore by looking into the sight opening or air gap 31 any drippage passing therepast when the device is not in operation will indicate faulty construction in the three way valve and plunger gaskets and the necessity for making immediate repairs.

The antisyphoning device 23 further comprises a water reservoir or tank 40 which is closed at its lower'end by a cap ll and a conduit connection 2 is shown in Fig. 2 attaching said cap to the pipe 9 in such manneras not only to provide communication therebetween but also it serves as an auxiliary support for the tank 40, a main clamp 43 being shown embracing the tank 40 and secured to the outside wall of the tub IS in any suitable manner to provide the main brace and support for the antisyphoning means.

A reduction coupling 44 is screwed onto the upper end of the tank 40 and into the upper end of the coupling is screwed the threads of the thimble 45 provided with the already mentioned sight openings or air gap 31, one end of the L connection 2 being screwed into the upper end of said thimble.

'Onto the externally threaded end of the thimble is first screwed an annular sump cup 46 before the thimble is finally screwed into the coupling 44 and after the latter connection has been made the cup 46 is screwed tightly against theupper face of the reduced part of the coupling, there being diametrically opposite holes 41 in the thimble to drain the sump when splash through the oppositely directed openings 31 from the liquid spirting past the openings collects in the sump cup.

Tank 40 is essentially made large owing to the fact that the discharge under pressure thereinto is greater than that egressing through the connection 42 into the drain pipe 8. The openlugs 31 are large, also are located far below the rim line of the tub so that overflow of backed-up sewage will flow out through said openings into a suitable receptacle placed there for that purpose before the tub proper could overflow thus indicating the feedback condition of the sewer.

the raised position and the valve 14 at such time is in the position placing supply line It in communication with pipe l8, the internal spring I6: would force the water out ofthe cylinder 20 and back into the main supp y line augmented by the suction pull. Should this condition arise simultaneously wherein the gasket 34 was defective and a backed-up condition of the drain pipe 9 was occurring, in such instance in all probability, impurities could be conveyed from the latter pipe through the line 2| into the cylinder 30 past such defective gasket 34 and into the main supply as aforesaid or similarly in apphcants patented device supra, were it not for some antisyphoning device like that of 23 placed in the path of flow. Such an antisyphoning device meets the requirement in connection with washing machines installed in localities demandingrigid enforcement of the sanitary code.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the subject matter claimed.

What is claimed is:

1. In a washing machine having a tub, a pipe for supplying water thereto, a cylinder fixed to and depending from the bottom of the tub, a plunger mounted t0 reciprocate vertically in said cylinder and carrying a basket movable in the tub, valve controlled conduit means for selectively connecting the bottom of the cylinder with the water supply pipe and with the upper part of the cylinder for respectively elevating the plunger and basket and for lowering the same, a tank supported exteriorly of the tub with its bottom end at a level below the bottom of the tub and its upper part at a level above the bottom of the tub, the upper part of said tank being provided with openings in the side walls thereof, a pipe connecting the upper part of said cylinder with the top of said tank so that matter discharged from the upper part of said cylinder will be caused to flow downward through and can be observed through the openings in the tank, and a pipe connecting the bottom of the tank with a sewer line.

2. In a washing machine having a tub and a fresh water supply line thereto, a cylinder secured to and depending from the bottom of the tub, a vertically reciprocating plunger mounted within said cylinder and spaced therefrom to provide an interior chamber, packing fixed about the lower end of said plunger, a basket'flxed on said plunger, a tank supported exteriorly of the tub with its bottom end at a level below the bottom of the tub and its upper part disposed in a position intermediate the top and bottom of the tub, said upper part of the tank having sight 1 openings in opposed sides thereof, a pipe concylinder with the supply pipe and to the pipe connecting with the upper part of the cylinder,

for respectively raising and lowering the plunger, a discharge pipe connected to the cylinder at approximately the level of the connection of the pipe connecting with the upper part of the cylinder, said discharge pipe having its opposite end connected to the top of said tank so that fluid discharged from the cylinder is caused to flow down past the sight openings in the upper part of said tank, and a pipe connecting the bottom of said tank with a sewer line.

RAYMOND W. WILSON.

REFERENCES CITED The following references are of record in the file of this patent:

6 UNITED STATES PATENTS Number Name Date Varney Dec. 15, 1925 Kendall Apr. 10, 1928 Sheridan June 5, 1934 Jewell July 3, 1934 Jewell Feb. 19, 1935 Woolley June 11, 1935 Boosey July 22, 1941 Stoddard July 29, 1941 Wilson Apr. 6, 1943 Paulson Nov. 27, 1945 Murphy Oct. 21, 1947 

